Insert Your Image in window7 login Background

Step 1: Open the Run dialog box and type regedit

Step:2
HKLMSOFTWAREMicrosoftWindowsCurrentVersionAuthenticationLogonUIBackground.
If the key does not exist, add a new DWORD value with the name OEMBackground.

Step: 3 Double click on the entry OEMBackground, and change the value from 0 to 1

Step: 4 Open C:windowssystem32oobe.
Step: 5 create a new folder named info, and open it.
Step: 6 Create a new folder within info named backgrounds.
Rename your desired wallpaper as backgroundDefault.jpg and place it inside the folder backgrounds (images must be less than 245KB in size).

Other Way

First download the free application  here,  run it.

Change Logon Screen” lets you browse to a new image, “Test” will bring up your logon screen

 

 Third way

You can also change the logon image and boot screen in win7 , vista and XP with  TUNE UP UTILITIES 2012.